Hawaii Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
830 AM EDT Wed Mar 16 2016

Valid 00Z Thu Mar 17 2016 - 00Z Thu Mar 24 2016

Latest guidance remains in better than average agreement through
the weekend.  Then some spread develops regarding the
speed/amplitude of an upper trough/leading front reaching the area
by the middle of next week.

Following the passage of a cold front, all guidance agree that
high pressure will build in from the northwest and will pass to
the north of the islands through the weekend into Monday. 
Moderate to fresh northeasterly trade winds will be in firm
control into Saturday and should begin to veer more easterly by
Sunday and into Monday.  However, GFS/ECMWF runs both show that
the front will stall just to the south with a lingering band of
relatively higher precipitable water values over/near the Big
Island where there may be slightly more shower activity than other
locations.  Passage of upstream shortwave energy and associated
front should bring drier air to the region during the weekend. 
From late Sun into Wed the 00Z ECMWF shows greater amplitude and
speed with an approaching upper trough versus other guidance. 
Given these differences, it is suffice to say that the chance of
showers will increase from west to east by the middle of next week.

Kong/Rausch